[randycat99]

I'll throw this curveball in there...it depends on how you rev in neutral, as far as getting a ferocious sound. As others above have noted, engine load is an important factor to be present, and the engine load is very light while in neutral (essentially, friction of lubricated metal engine parts is the only load). However, there is a short moment where engine load can be appreciable, right at the beginning of poking the gas pedal. In that scenario, the engine load is its own inertia as it goes from idle rpm to some higher rpm. So if you rapidly go from idle to 3000 rpm or so, the rotational inertia of the moving parts of the engine will be appreciable, which will present a temporary engine load. So give a healthy poke to the throttle, just long enough to give a quick rise in rpm, but not so uncontrolled it spikes up to hit a rev limiter. The goal is to leverage inertial engine load at the very beginning, and then letting the rpms fall back to normal idle. I believe you will be employing enough throttle at that point to give a very nice sound.